Various methods for the automatic sewing of a succession of material workpieces along one edge has become known. With these methods the material workpieces are either laid by the operator directly under the presser foot or they are fed to a feed station situated in front of the sewing machine and then automatically fed into the sewing machine.
In the instance where the material workpieces are laid directly under the presser foot the object of the sewing installation depends mainly upon the skill of the operator, that is, while the material is placed beneath the sewing machine presser foot the sewing machine itself is standing still thus no productivity is possible. It has already been proposed to connect a feed station in front of the sewing machine. Even with a feed station connected in front of the sewing machine the amount of time yielded to the operator is only equal to that amount of time which it takes for the feed mechanism to advance from its forward position to its backward position and the operator is dependent on this cycle time.
It is also known in the art for the operator to place the material workpieces on a continually running belt which advances the same into the sewing area. With this method, which is also considerably influenced by the cycle time of the sewing machine, the pieces of material must be laid on the moving support exactly as they are to be presented to the sewing instrumentalities. As may be appreciated, with this type of device it is more difficult to align the pieces of material workpieces in the correct manner and is greatly dependent upon the skill of the operator.
Yet another type of device which has been known in the art is to place the material within a plurality of clamps which are rotated underneath the sewing machine and feed the material thereto. With this installation the time for loading the clamps is dependent upon the cycle time of the sewing machine. Furthermore, a device of this sort is suitable only for small pieces.